Internal-combustion engine casing construction



Aug. 4, 1953 I M. WARE 2,647,494

INTERNAL-COMBUSTION ENGINE CASING CONSTRUCTION Filed'April 19. 1949 3Sheets-Sheet 1 7 CIIIIIIIIIII,

' INVENTOR. BY Mflw m fmzzdza ATTORNEYS Aug. 4,' 1953 M. WAREINTERNAL-COMBUSTION ENGINE CASING CONSTRUCTION Filed April 19. 1949 3Sheets-Sheet 2 INVENTOR.

ATTORNEYS M. WARE INTERNAL-COMBUSTION ENGINE CASING CONSTRUCTION FiledApril 19. 1949 Aug. 4, 1953 5 Sheets-Sheet 3 INVENTOR.

ATTO RN EYS Elle Patented Aug. 4, 1953 INTERNAL-COMBUSTION ENGINE CASINGCONSTRUCTION Marsden Ware, Huntington Woods, Mich., as signor to PackardMotor Car Company, Detroit, Mich., a corporation of Michigan ApplicationApril 19, 1949, Serial No. 88,246

1 Claim.

This invention relates to internal combustion: engines and particularlyto an improved crankcase construction for an internal combustion en gineof the high speed type.

Numerous attempts have heretofore been m de to develop an enginecrankcase which at one time is sufficiently rigid to resist distortionresultin from the application thereto of forces from the associatedcrank shaft and of such light weight that the engine may be utilized inaircraft or in any other vehicle or place where it is important tomaintain the ratio of weight to horsepower as low as possible. It hasbeen suggested that such a crankcase may With advantage be fabricated ofnon-ferrous metals, that the walls and webs be relatively thin, and thatelements of high tensile strength be utilized in association with thetransverse webs for the purpose of placing the metal of the webs underinitial compression and for ensuring that those webs, and the crankcasegen-' erally, are not subjected to excessive strains resulting from thetransmission thereto, from the crank shaft, of impressed forces whichvary widely in direction, magnitude and point of application as thesupported crank shaft revolves athigh speed.

The present invention contemplates an internal combustion enginecrankcase which embodies, in association with the transverse webs of thecas ing, tension members of the general type heretofore proposed, suchmembers, however, being so disposed in relationship to the webs withwhich they are associated that each such web has great strength for itsweight, and theengine casing as a whole has the greatest possiblerigidity for a I.

given weight and given engine power.

- While the invention may be employed with advantage in the crankcaseconstructions of engines of widely varying types, it is perhaps ofgreatest utility when incorporated in an engine casing in mounted uponand housed largely within such extension. The engine casing webs extendtrans.

versely of the axis of the casing and the lower portion of such web, towhich a crank shaft bear-"- ing isimmediately secured, is especiallysubject to strain due to crank shaft forces imposed thereon;

I It is of first importance, therefore, that this portion of each web bedesigned and constructed in such manner that it may successfully resistall imposed forces without at the same time being so -heavy in sectionthat the weight of the engine casing as a whole becomes excessive.

The present invention contemplates the application of tensioning membersto those portions of the casing webs located within the crankcase bodyin such manner that substantially all portions of this web are placedunder initial compression and are supported adequately at all times. Thereinforcing elements or tension rods pass through the web in variousdirections and'preferably two tension members extend transversely of theweb, one above and one below the crank shaft bearing and two aredisposed vertically, one to either side of the crank shaft bearing. Inevery instance, however, the reinforcing element is located Within anelongated cylindrical aperture of continuous nature formed in the webwith which the element is associated, the web being enlarged orthickened where necessary to provide a section adapted to be pierced bysuch an aperture.

The tension rods are so formed that each makes contact at several pointsalong its length with the wall of the cylindrical aperture through whichit extends, in order to prevent any vibration of the rod relatively tothe web, and the tensioning elements extend completely through the web.No tension rod has threaded relationship with the web with which it isassociated but each is provided with a head at one end and a nut at theother, or with nuts at both ends, to engage the lvention selected fordisclosure by way of exa pl Figure 1 is a transverse section through theengine crankcase, the section being taken intermediate two cylinders;

Figure 2 is a similar section, taken on the axis of one of thecylinders;

Figure 3 is a longitudinal section through a portion of the enginecasing, showing the crank shaft and several cylinders in elevation, theconnecting rods being broken away;

. Figure 4 is a top plan view of a portion of the crankcase withattached cylinders;

. Figure 5 is a section on line 5-5 of Figure 1;

Figure Sis a section on line B6 of F gure 2;

' to laterally deflect.

Figure 7 is a section on line 'l-J of Figure and Figure 8 is a sectionon line 8-8 of Figure 6.

The body of the engine casing is generally indicated at B, the upwardextension thereof at E and the oil retaining pan, suitably attached tothe body B, is indicated at P. The side walls 10 and H of the casingbody are upwardly and inwardly curved from elevations just above thelower terminal flanges 12 and I3, to which the pan P is attached, andthe lower edges of the flat inclined outer walls Hi and I5 and likewisethe lower edges of the parallel vertical inner walls I6 and ll, of thecrankcase extension E, are integral with the upper margins of the sidewalls, as shown in Figures 2 and 3. The converging walls l4 and I6 mergeat their upper ends to form an elongated solid section I 8 and likewisethe upper margins of the converging walls 55 and IT merge to form anelongated solid section 19.

The side walls It and H of the crankcase body B are connected bybridging webs W and each of these webs has an upward extension orprolongation W which bridges and connects the side walls l5 and ll ofthe crankcase extension E, one such bridging web being shown, mainly inelevation but partially broken away, in Figure 1 of the drawings, andseveral being shown in section in Figures 3, 6 and 7. The body B of thecrankcase is of steel or lighter non-ferrous metal and is formed by acasting operation so that the side walls and transverse webs areintegral parts of a rigid structure. The lower or major portion of eachsuch web constitutes a support for the upper half of a crankcase bearingsleeve, indicated at 25, the lower half of sleeve 25 resting upon andbeing supported by the bearing block 26 which is generally rectangularand fits closely within a downwardly opening rectangular recess formedin the lower portion of the associated web.

The tensioning rods employed in association with each web are, in theform of the invention illustrated, four in number, two being disposedvertically and two horizontally, the vertically recesses which receivethe vertical tension rods 28 and 29 are disposed equi-distantly from theaxis of the crank shaft bearing 25 and upon opposite sides thereof.

As most clearly shown in Figures 6 and 7 the axes of these tensioningmembers are located in a vertical plane which bisects the associatedsymmetrically formed web. The tension members 30, of which there are twoassociated with each web, and the two adjacent tension members 3!, aredisposed in horizontally extending parallel cylindrical apertures formedin horizontally extending thickened portions of the web which may bemost clearly seen in Figure 3 of the drawings, the tension rods of eachpair being disposed upon opposite sides of the vertically extendingtension rods 28 and 29, as may be most clearly perceived in Figures 5and 7.

It will thus be seen that the crank shaft bearing block 26 is pierced byfour cylindrical ten- The elongated cylindrical sion rod receivingapertures, two to receive horizontal tension rods 3| and two to receivevertical tension rods 28 and 29, and it is thus firmly supported,becoming, in effect, an integral portion of the web after the assemblyhas been completed. Tension rods 28 and 29 are provided at their upperends with integral heads 28a and 23a and at their lower ends with lockwashers 28b and 29b and nuts 28c and 290. The tension rods 3| areprovided with integral heads 3la, lock washers Sit and tightening nuts3lc, rods 30 being of similar type. Each rod receiving aperture extendsfrom one edge of the web with which it is associated entirely throughthe web to the opposite edge so that, when tension is applied to thetension rod positioned within that aperture by turning the tensioningnut provided, the metal of the web intermediate the head and tensioningnut of each rod is placed under compression.

By reason of the fact that the tensioning rods are disposed in themanner described, with a plurality of rods extending transversely ofeach web, and a plurality extending vertically therethrough, practicallyall portions of each web are placed under compression and those portionsof the web in the immediate vicinity of the crank shaftbearing 25 are,in particular, placed under compression. As a result, and further byreason of the fact that each web is reduced in thickness where the forceof compression applied thereto are of reduced amplitude, an extremelyrigid support for the crank shaft bearing is provided the weight ofwhich, however, is the lightest possible for a crankcase having therequired strength and rigidity.

Each of the engine cylinders is indicated generally at A and is providedwith a peripheral flange A which rests upon the horizontal head H of theupwardly extending portion E of the casing, the flanges A being securedto the casing by bolts 35 which enter recesses formed in the ribs i8 andIQ of the casing and bolts 38 which have threaded engagement with thethreaded walls of bolt receiving apertures formed in the web extensionsW. Projecting upwardly from the upper surface of each cylinder end Wallare a plurality of bosses 38 each having an upwardly facing annularshoulder adjacent its upper end. A circular plate 39 is provided with aseries of apertures which receive the reduced upper ends of thesebosses, the plate resting upon the shou ders of the respective bossesand being welded to each by a circular weld. There is thus provided atthe end of the cylinder a water space and this space is in opencommunication with a water space of annular cross section defined by theouter surface of the cylinder wall and the cylindrical jacket 48 weldedto the periphery of plate 39 and to an upwardly projecting circularflange integral with the main cylinder flange A.

The lower end of each cylinder is housed within the crankcase extensionE and a second water space is defined by the cylinder wall surfaces, theinner faces of walls 5 and H, the flanges A and the water sealing meansincluding a plurality of sealing rings M, 42 and 43 encircling the lowerend of each cylinder. Intermediate sealing rings 42 and 43 of eachcylinder is a leakage collection groove 44 within which gathers anywater which may happen to leak downwardly past seals 4| and 42, anyleakage entering groove 44 escaping through drainage duct :35. The upperand lower water spaces communicate with each other through passages 46formed in the cylinder flanges A.

If desired the several tension rods 28, 29, 30 and 3| may be of uniformsection from end to end but are preferably formed as shown in thedrawings, the major portion of each rod being, in section, smaller indiameter than the cylindrical aperture through which it extends andbeing provided with enlargements which maintain it in coaxialrelationship with the aperture within which it is housed. These severalrod enlargements are indicated at 28d, 29d, 30d and 31d, respectively.By so constructing the tension rods ease of assembly of the rods andwebs is promoted.

The crankcase and cylinder construction described and illustrated issimple in design but of great eificiency in actual operation. The metalof that portion of each web which lies within the crankcase proper isunder initial compression, as explained, substantially in its entiretydue to the conjoint action of the angularly disposed sets of tensionrods and the webs are light in section even though subjected tosubstantial, rapidly repeated, forces constantly varying in direction,imposed thereon by the crank shaft. The cylinders are most securelyattached and the simple cooling means formed by assembling the severalparts in the manner described is thoroughly effective.

Having thus described the invention, what is claimed as new and desiredto be secured by Letters Patent is:

In an engine, an elongated crankcase comprising a body portion and anupward extension terminating in a flat cylinder flange receivingsurface, said body portion and extension having transversely spaced sidewalls respectively, the side walls of the extension being upwardcontinuations of the side walls of the body, a plurality of parallelwebs disposed transversely of the crankcase and rigidly connecting theside walls of both body and extension, each web having a recess in itslower edge to receive a hear.- ing block and having two parallelvertically disposed passages extending therethrough from said recess tosaid cylinder flange receiving surface, each web having also a pluralityof horizontally disposed passages therein, two such passages extendingthrough each side wall and adjacent portion of each web to the bearingblock recess formed in that web, and each such horizontal passage on oneside of said recess being aligned with one on the other side of therecess, and said pairs of aligned passages being parallel to and onopposite sides of, a plane which includes the axes of the verticallyextending passages of the same web, a bearing block in each such recess,each block having two horizontal passages therethrough which register,respectively, with the aforementioned aligned horizontal passages in theweb, and two vertical passages which are aligned with and formcontinuations of the vertical passages inthe web, and tension rodsdisposed within the aligned passages of bearing blocks andwebs and maintaining the blocks and webs in compression.

MARSDEN W ARE.

References Cited in the file of this patent UNITED STATES PATENTS GreatBritain Mar. 3, 1927

